THE following letter seems to me so valuable, and the accuracy of
the statements vouched for by so high an authority, that I have
obtained permission from Dr. Huggins to send it for publication.1 No one
who has attended to animals either in a state of nature or
domestication will doubt that many special fears, tastes, &c.,
which must have been acquired at a remote period, are now strictly
inherited. This has been clearly proved to be the case by Mr. Spalding
with chickens and turkeys just born, in his admirable article recently
published in Macmillan's Magazine.2 It is probable that most
inherited or instinctive feelings were originally acquired by slow
degrees through habit and the experience of their utility; for instance
the fear of man, which as I showed many years ago, is gained very
slowly by birds on oceanic islands. It is, however, almost certain that
many of the most wonderful instincts have been acquired independently
of habit, through the preservation of useful variations of pre-existing
instincts. Other instincts may have arisen suddenly in an individual
and then been transmitted to its offspring, independently both of
selection and serviceable experience, though subsequently strengthened
by habit. The tumbler-pigeon is a case in point, for no one would have
thought of teaching a pigeon to turn head over heels in the air; and
until some bird exhibited a tendency in this direction, there could
have been no selection. In the following case we see a specialised
feeling of antipathy transmitted through three generations of dogs, as
well as to some collateral members of the same family, and which must
have been acquired within a very recent period. Unfortunately it is not
known how the feeling first arose in the grandfather of Dr. Huggins's
dog. We may suspect that it was due to some ill-treatment; but it may
have originated without any assignable cause, as with certain animals
in the Zoological Gardens, which, as I am assured by Mr. Bartlett,3 have
taken a strong hatred to him and others without any provocation. As far
as it can be ascertained, the great-grandfather of Dr. Huggins's dog
did not evince the feeling of antipathy, described in the following
letter.

CHARLES DARWIN

1 William Huggins (1824-1910), astronomer, his letter was printed on pp. 281-2. Huggins' letter gives an account of three generations of dogs which exhibited fright when in the vicinity of a butcher or butcher's shop. Further letters on the subject appeared in Nature (20 February 1873), pp. 303 and 20 March 1873, pp. 377-8.